Encapsulated bleaching agent particles
A shelf-stable liquid agent or detergent containing a bleaching agent in the form of a finely particulate bleaching agent encapsulated in a crosslinkable polymer matrix.
1. A method of manufacturing a bleaching agent granule, comprising the steps of:
forming an aqueous mixture in which a finely particulate bleaching agent, hollow microspheres, and a water-soluble crosslinkable polymer are dispersed;
adding droplets of the aqueous mixture to an aqueous solution containing a cross-linking agent for the crosslinkable polymer, thereby crosslinking the cross-linkable polymer to form capsules comprising the particulate bleaching agent and the hollow microspheres encapsulated in a matrix of the cross-linked polymer; and
removing the capsules from the aqueous solution of the crosslinking agent.
2. The method of claim 1 , wherein the aqueous mixture comprises 1 to 60 percent by weight of the dispersed finely particulate bleaching agent.
3. The method of claim 1 , wherein the particulate bleaching agent is a peroxycarboxylic acid, a diacyl peroxide, or a mixture thereof.
4. The method of claim 3 , wherein the peroxycarboxylic acid is an imidoperoxycarboxylic acid.
5. The method of claim 4 , wherein the imidoperoxycarboxylic acid is 4-phthalimidoperoxybutanoic acid, 5-phthalimidoperoxypentanoic acid, 6-phthalimidoperoxyhexanoic acid, 7-phthalimidoperoxyheptanoic acid, N,N′-terephthaloyl di-6-aminoperoxyhexanoic acid, or a mixture thereof.
6. The method of claim 3 , wherein the diacyl peroxide has a formula of R′—C(O)—O—O—C(O)—R″, in which R′ and R″, mutually independently, each denote an alkyl group having 8 to 20 carbon atoms.
7. The method of claim 6 , wherein the diacyl peroxide is di-n-decanoyl peroxide, di-n-undecanoyl peroxide, dilauroyl peroxide, or a mixture thereof.
8. The method of claim 1 , wherein the aqueous mixture comprises 0.01 to 5 percent by weight of the water-soluble crosslinkable polymer.
9. The method of claim 1 , wherein the water-soluble crosslinkable polymer is an ionotropically crosslinkable polymer.
10. The method of claim 9 , wherein the ionotropically crosslinkable polymer is carrageenan, alginate, gellan gum, or a mixture thereof.
11. The method of claim 10 , wherein the ionotropically crosslinkable polymer is sodium alginate.
12. The method of claim 1 , wherein the aqueous mixture contains a stabilizer for the bleaching agent.
13. The method of claim 1 , further comprising encasing the capsules containing the particulate bleaching agent with a paraffin wax.